Electrical Machines Objective Questions – Set 8

The speed regulation of a DC motor is given as

In case of a DC Shunt motor if the load is decreased to some extend, what will happen to its speed?

In a DC series motor, if the armature current is reduced by 50 %, the torque of the motor will be equal to

Which of the following represents the pitch factor?

The function of field regular in a DC compound motor is to

The direction of rotation of a DC compound motor can be reversed by interchanging

In speed control of DC shunt motor by varying field flux, what may be the value of field regulator?

The speed of a DC series motor is

The current drawn by a 220 V DC series motor of armature resistance 0.5 Ω and back back emf 200 V is

A 3-phase, 2 pole, 12 slot synchronous machine is operating at synchronous speed. Find the slot angle?

What will happen if the the supply terminals are reversed in case of a DC shunt motor?

In a DC Shunt Motor the speed can be increased by

Ward-Leonard system for controlling the speed of a DC motor is used where

If in DC Shunt Motor the flux is reduced suddenly to zero, then

A DC series motor has which of the following characteristics?

The DC compound motors are generally

In Ward-Leonard method of speed control, the directional of rotation of motor is reversed usually reversing the connection of the

A 220 V DC machine has an armature resistance 1 Ω. If the full load current is 20 A, the difference of induced voltage between generator and motor is

If the load current and flux of a DC motor are held constant and voltage applied across its armature is increased by 5%, the speed of the motor will

The speed of a cumulatively compound DC motor can be controlled by varying

Which of the following is done in speed control of DC motor by field flux control?

If a DC Series motor is connected across an AC supply it will

If the flux of DC motor approaches zero, its speed will

In a DC compound motor the field regulator is provided to

In case of a compensated DC series motor, the compensating winding is provided

Consider a separately excited DC motor. If the field current is increased while the armature terminal voltage is held constant, then speed of the motor will

In field flux method speed control of DC Motor is

The type of DC motor generally used for shears and punches is

The armature shaft must be able to withstand

In DC Shunt Motor has an disadvantage of